My 2004 F150 is in the shop right now. They replaced the timing chain and fazers because of something coming apart. I didn't totally understand what the Mechanic was talking about. Anyway, now that these parts are replaced my truck won't start. It runs for about 2 seconds and dies and will crank ok after that. What have these guys done to my poor little V8?

look at fuel pressure and see if you have spark